Kristen Smith, 31, of Colorado, was found guilty of kidnapping her 5-day-old nephew, Kayden Powell, and driving him across state lines in early February.

Smith was on trial in federal court this week, and took the stand Wednesday in her defense.

Kayden was found about 30 hours after he went missing inside a frost-covered plastic bin behind a gas station in Iowa.

Smith testified Wednesday that she suffered a miscarriage in January two weeks before her half-sister, Brianna Marshall, gave birth to Kayden.

Smith said Marshall planned to move herself, her baby and the baby's father to Colorado to live with Smith. Smith testified that when she awoke to leave Beloit the day Kayden was reported missing, Kayden's father told her to take the baby with her. Smith said when Marshall called her at about 4:30 a.m. Smith told Marshall Kayden was with Smith. When police called Smith asking her to pull over, Smith said she wasn't thinking straight at that time.

The trial was halted briefly Wednesday afternoon after Smith began sobbing uncontrollably on the witness stand.

An FBI agent who testified for the prosecution Wednesday morning said Smith's car was packed with baby clothes, a car seat and a stroller. Smith testified in court that the baby items in her car were placed there by Kayden's parents. The bin Kayden was found in alive on Feb. 7 was also put in Smith's car by Brianna and Kayden's father, Smith testified. The police chief who found Kayden inside the bin testified Tuesday that the lid was clamped shut and frost had formed on top.